Today marks one year since Microsoft Corp. announced its acquisition of Yammer, the leading provider of enterprise social networks. Since the acquisition, Microsoft's enterprise social momentum has accelerated in all areas, including new users, paid customers, user engagement, innovation, and the ecosystem of partners selling and connecting to the Yammer platform. Twelve-month growth highlights include the following: Registered users have grown by more than 55 percent to nearly 8 million. Paid networks increased more than 200 percent year over year. Yammer user activity (i.e., messages, groups and files) has approximately doubled year over year.